Summary On 09 April 2003, a Robinson R44helicopter, registrationC-GRDI, serial number0900, departed on a local familiarization flight from the Trek Enterprises facility, approximately 10nautical miles southeast of Peace River, Alberta. The pilot-in-command was accompanied by the company's chief pilot designate, who was on-board to acquaint himself with the pilot and the aircraft. After a series of circuits, the helicopter was flown to the company's practice area where a number of practice autorotations with power-on recoveries were conducted. At least twice during these exercises, the engine rpm was allowed to exceed the prescribed limit. During the fourth autorotation, while the helicopter was being flown by the pilot-in-command, the airspeed and rotor rpm decreased to such a point that the helicopter could not maintain flight and subsequently crashed into a treed area. The helicopter was substantially damaged; there was no post-impact fire. Both pilots suffered severe injuries to their lower extremities. The accident occurred at approximately 1515 mountain daylight time. The search and rescue satellite system reported an emergency locator transmitter activation and was able to calculate an accurate site location on the second sweep. The helicopter was found by the owner at about 2000 mountain daylight time using a neighbouring company's helicopter. The pilots were evacuated to the Peace River hospital, and then to facilities in Edmonton, Alberta. Ce rapport est galement disponible en franais. Other Factual Information The occurrence flight was preceded earlier in the morning by a familiarization flight with the pilot and the company owner/operations manager, a non-pilot, on-board. This flight lasted approximately one-half hour and consisted of circuit practice and local area flying. After lunch, the pilot-in-command (PIC) departed with the chief pilot designate (CPD) on another familiarization flight. The PIC had been operational with the company the previous year and was scheduled to begin operational flying again within the next two days. CPD, for his impending position as chief pilot and training pilot, was a passenger on the flight, getting to know the PIC and gaining some experience on the R44helicopter. The flight was not intended to be a training flight, and neither pilot engaged in a pre-flight briefing to discuss flight training concepts and procedures. During the flight, the CPD asked to see some flight demonstrations, particularly, autorotation exercises with power-on recoveries. The PIC had some misgivings about conducting the exercises, but his perception was that the CPD possessed sufficient helicopter experience to ensure the safety of the flight. He was also cognizant of the CPD's impending appointment as chief pilot. The CPD proceeded to demonstrate the first autorotation with the PIC following through on the controls. During the power-on recovery, the CPD asked that the power be checked. The PIC noted that the throttle was not fully open and proceeded to apply full throttle. At this time, an engine overspeed condition in excess of 114%was observed, with corresponding main rotor overspeed (the gauge limit is114). A subsequent autorotation resulted in the PIC inducing a second overspeed condition of about110%. On the fourth autorotation, with the PIC flying, the helicopter's airspeed was allowed to decrease to approximately 50knots during a right-hand turn toward the practice field. At this time, the low rotor rpm horn sounded, and the cyclic and collective controls began to move erratically. The CPD did not intervene, as he was unfamiliar with the helicopter, and he assumed that the PIC had the helicopter under control. The helicopter then descended into a wooded area adjacent to the practice field and struck the ground. The R44 possesses a low-inertia main rotor system, and the Aircraft Flight Manual (AFM) recommends that practice autorotations be conducted at 70knots indicated airspeed. There is also the caution that during simulated engine failures, a rapid decrease in rotor rpm will occur, requiring immediate lowering of collective control to avoid dangerously low rotor rpm. Robinson Safety Notices (SN) SN10, SN20, SN24 address the issues of low rpm rotor stall in R44helicopters. No reference was found regarding overspeed restrictions in the AFM, with the maximum allowable engine rpm of 102%(2692rpm) being specified in the limitations section. The Robinson Maintenance Manual ModelR44 (MMR44), Section2.540, refers to Textron-Lycoming Service Bulletin369 which states that for rotary wing aircraft using Textron-Lycoming engines, no momentary overspeed is allowed. MMR44, Section2.540, also addresses different levels of rotor system overspeeds and the inspection criteria for each level. The PIC was aware of the restrictions but, in spite of his misgivings, decided to continue with the flight. The PIC held a valid commercial pilot licence (helicopter), was endorsed on the R22andR44, and was awaiting endorsement on the Bell206 (BH06) helicopter. He had a total flight time of approximately 375hours, of which about 270hours were on the R44, including 56hours flown the previous season from April2002 to September2002. He had completed a company pilot proficiency check flight on the R44on 26April2002. From January2003 to March2003, the pilot had completed 20hours of flight training on a BH06 toward a type endorsement. The BH06differs from the R44in that it has a high-inertia main rotor system whereby the rotor rpm does not decrease as rapidly with airspeed and power changes as that of theR44. He was scheduled to begin flying operationally on 11April2003 and had not been at the controls of anR44 since he left the company at the end of the flying season inSeptember2002. Under existing regulations, the PIC met the requirements of Canadian Aviation Regulations (CARs)401.05 concerning pilot recency and currency. The flight crew member qualifications under CARs703.88 and the Company Operations Manual (COM)2.15 were also met, in that the required three take-offs and landings had been completed during the training undertaken on the BH06. Sufficient take-offs and landings in the R44were accomplished during the previous flight with the operations manager and the subsequent flight prior to the autorotation exercises. Neither the CARs nor the COM require a review of emergency procedures in order to meet the flight crew qualification beyond the annual pilot proficiency requirement. Annual company recurrent training (COMsection5.6.8) refers to the program outlined in the initial pilot training program. No reference is made to the seasonal nature of the work where pilots have not been flying for a considerable period of time. The CPD held a valid airline transport pilot licence (aeroplane) and a commercial pilot licence (helicopter) with endorsements on 10different types of helicopters. His total flight time was 8652hours on fixed-wing aircraft and 6023hours on helicopters. He had recently returned to helicopter flying after having flown primarily fixed-wing aircraft for the previous 2years. In the last year, he had accumulated about 150hours of flight time, of which 15hours were on helicopters, including 6.5hours on the BH06. About four of the hours were flown in the week preceding the occurrence flight while he completed a self-directed training program on the BH06B with the company's former chief pilot. He was hired by Trek Enterprises on 02April2003 and was scheduled to conduct a Transport Canada pilot proficiency check ride in the near future for his approval in the position of chief pilot. He had no experience with, nor was he certified on, theR44helicopter. Weather conditions reported at 1500 mountain daylight time for the Peace River Airport were as follows: winds 330T at 13knots, gusting to 20knots; visibility 15statute miles in light rain and snow showers; broken cloud 3000feet above ground level, temperature 5C, dew point minus 2C; altimeter setting29.68, with an observed rising trend throughout the day. Weather was not considered to be a factor in this occurrence.